#include<stdio.h>
int main(){
    int a,b,c;
    printf("enter the lengths of the threee side of thr triangle(a,b,c): ");
    scanf("%d %d %d",&a,&b,&c);
    if(a==b && b==c{
    printf("Equilateral.\n");
    }else if(a==b ||b==c||a==c|){
        printf("lsosceles.\n");
    }else if (a<0||b<0||c<0){
        printf("invalid input.\n");
    }else{
        printf("Scalene".\n);
    }
    return 0; 
    
}